Work roll sensing and/or balancing arrangements

ABSTRACT

In a rolling mill stand having housing means, window means in the housing means, and a pair of work rolls having bearing chocks for rotatably supporting the ends of the work rolls in the window means, the disclosed combination comprises at least one extension on each of the bearing chocks, position sensing means disposed generally between a pair of the work roll extensions which are respectively and spacedly disposed on a juxtaposed pair of the work roll chocks, means for removably mounting the sensing means on the mill stand, and means for bearingly and respectively engaging movable components of the sensing means with the pair of roll chock extensions for movement therewith.

a waited States Patent 1191 [111 3,733,875 Steimer [451 May 22, 1973 [54] WORK ROLL SENSING AND/0R 3,018,676 1/1962 Polakowski ..72 21 BALANCING ARRANGEMENTS 3,651,679 3/1972 Shumaker ..72/238 [75] Inventor: Robert G. Steimer, West Mifflin, Pa. Primary Examiner Milton Mehr [73] Assignee: Mesta Machine Company, Attorney-Donn Smith Homestead, Pa. [57] ABSTRACT [22] F1led: July 12, 1971 In a rolling mill stand having housing means, window [21] PP N05 161,540 means in the housing means, and a pair of work rolls having bearing choeks for rotatably supporting the 52 us. (:1. ..72/237, 72/21, 72/237 of the mus in the wind means, 51 1m. 01 ..B2lb 37/00, B21b 31/08 closed combinam. mPriSes 9? .extensmn [58] Field of Search ..72/21 237 238 each the warm Sensmg means disposed generally between a pair of the work roll extensions which are respectively and spacedly disposed on a 'uxta osed air of the work roll chocks, means [56] References cued for relnova laly mo unting the sensing means on the mill UNITED STATES PATENTS stand, and means for bearingly and respectively engaging movable components of the sensing means with 3,532,371: 61970 Stol1l1e the pair of ol] chock extensions for movement ,2 ,5 91965 Hu seta. /l6 3,431,762 3/1969 OBrien ....72/240 X therewith 3,353,385 1 H1967 Neumann et al. ..72/2] 20 Claims, 7 Drawing Figures PATENTEU Z 1975 733 875 SHEEI 1 OF 3 INVENTOR.

ROBER G. STEIMER BY a HIS ATTORNEY PATENTEWZZ'W 3.733.875

SHEET 2 OF 3 INVENTOR.

HIS ATTORNEY WORK ROLL SENSING AND/OR BALANCING ARRANGEMENTS The present invention relates to rolling mills, and more particularly to work roll sensing and or balancing arrangements for a rolling mill. An advantageous feature of the invention is the facility with which the various components thereof can be inserted, inspected, and removed from a given mill stand of the rolling mill.

While the present invention is useful in connection with many types of rolling mills, for the purpose of elucidating the invention an application thereof to a four high strip mill has been described.

The invention also is described in conjunction with the Mae West type mill housing, as described and claimed in the US. Pat. to H. J. Kalberkamp No. 3,204,443 of common assignment, which thereby affords a convenient means of mounting the gap sensing arrangement. It will be understood, however, that other types of mill housings can be employed in accordance with the teachings of the invention.

In recent years ever higher strip speeds have been in vogue in the development and operation of rolling mills. At the same time much thought has been given to the production of strip within very close thickness tolerances. Various types of automatic gauge control systems have been developed with a view to limiting the variation in strip thicknesses to a range within the aforementioned tolerances. While these systems have taken a number of different forms, they incorporate power-driven screwdowns of the mill housings to compensate for tendancies of the work roll gap to vary. In the case ofa hydraulic rolling mill, the mill housing cylinders can be adjusted for a similar roll gap compensation.

Various types of sensing means have been employed in conjunction with the mill housing screwdowns or equivalent for the purpose of supplying a control signal to the power equipment associated with the screwdowns or housing cylinders. One form of such sensing means is the familiar x-ray gauge which usually is mounted eight feet or more down stream on the delivery side of the mill stand. Because of the considerable transport time involved, the high speed of the strip notwithstanding, the signal generated by the x-ray thickness gauge or other gauge similarly located, reaches the screwdown only after a considerable length of the strip has been exposed to an undesirable roll gap condition. The response of the automatic gauge control is therefore sluggish and conducive to continuous hunting.

Another arrangement the work roll gap sensor takes the form of load cells placed directly between individual backup roll chocks, or between one or more of them and the mill stand housings. In these locations unfortunately, the load cells are insensitive to a number of conditions which have a bearing upon the work roll gap conditions, for example roll flatening at the contact areas between the backup rolls and the work rolls, and mechanical and lubricant distortions at the back-up roll chocks. In addition, load cells are relatively inaccurate and in some configurations must be employed in conjunction with biasing means such as a heavy spring, which introduces further inaccuracies. The use of load cells, then, either alone or in conjunction with the aforementioned x-ray gauge to signal roll gap conditions thus does not offer much improvement in terms of response and accuracy of the gauge control apparatus.

In addition to the aforementioned x-ray gauges and load cells, other types of sensors have been attached to the back up roll chocks or to the work roll necks. All of these conventional dispensing arrangements lack one or more of the following requirements: high accuracy, high repeatability, fast response, independence from mill modulus, ability to detect roll eccentricity, ability to detect dynamic influences of speed upon strip gauge, and non-interference with work roll changes (i.e. without electrical or mechanical disconnections or physical adjustment). The present invention unexpectedly meets all of these requirements.

Ideally the most accurate mode of sensing work roll gap conditions would be the insertion of a sensor directly into the work roll bite. This would eliminate the effects of transport time along with variables caused for example by back-up roll eccentricities, bearing oil film, and the various deflections and other distortions which enter into the mill modulus, such as housing spring, roll flattening, fluid compression, and the like. It is obviously impractical to mount a sensor directly between the work rolls, and the closest approximation of this ideal condition is to place one or more sensors between the work roll chocks. Transport time is thereby eliminated along with the aforementioned variables including all distortions in mill modulus, with the exception of work roll flattening at the bite or gap. Location of the work roll gap sensors between the work roll chocks senses all other variables, such as those mentioned previously, so that errors caused by these variables are corrected. With the work roll sensors of the invention conventional load cells can be installed in the usual manner to supply a signal of mill stand pressure, and this signal can be used to modify the roll gap signal produced by the work roll chock sensors in order to account for work roll flattening. As work roll flattening is a very small portion of the overall mill modulus variations, any error caused by faulty or belated load cell signals are very insignificant.

As the work rolls determine the roll bite, sensing of work roll position is a convenient and practical method of sensing strip thickness. In the sensing arrangement of the present invention, work roll position is established by measuring the position of the work roll chocks.

As there is the possibility of slight misalignment of the work roll checks from a condition of precise parallelity, gap sensing means desirably are employed between each side of the work roll chocks. The average of the readings thus obtained can then be employed as the gap signal.

Finally the gap sensing means, and also the work roll balancing means when used, are structurally arranged and located in avoidance of the work roll assembly, when the latter is inserted or withdrawn through the mill stand window. When employing certain forms of balancing means, such as those disclosed herein, the sensing means can be conveniently but unexpectedly mounted on the balancing means.

I am aware of the US. Pat. to J. W. OBrien No. 3,431,762 who discloses use of load cell means directly between the work roll chocks of the mill stand. However, this arrangement does not provide for ready inspection, maintenance removability, or replaceability of the load cells or of work roll balancing means. Re-

moval of the'work roll assembly moreover is interfered with as described hereinafter. In order to accommodate changes in work roll diameters, the known arrangement would require changes in load cells, the load cell springs, or both, or the use of elongated springs which would introduce further inaccuracies. In contrast to another feature of my invention, there is no provision for mounting the gap sensing means on the housing to facilitate removal of the work roll assembly. In contrast to still other features of my invention there is no provision for mounting of the gap sensors in conjunction with work roll balancing devices, or for mounting either of these on the mill stand housing, or otherwise for ready removability relative to the work roll assembly.

I overcome the disadvantages of the prior art and accomplish the aforedescribed desirable results, in a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting the ends of the work rolls in said window means, by the combination comprising at least one extension on each of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spaceclly disposed on a juxtaposed pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith.

I also desirably provide a similar combination wherein means are provided for suspending said sensing means generally between said pair of chock extensions.

I also desirably provide a similar combination ancing device for bearingly engaging said pair of extensions.

I also desirably provide a similar combination wherein said engaging means include a pair of opposed plungers disposed for bearing contact with said extensions, and said movable components of the sensing means are secured to said plungers respectively for movement therewith.

I also desirably provide a similar combination wherein said housing protrusion extends generally between said pair of chock extensions, and said balancing device is mounted on said housing protrusion at a location between said extensions.

I also desirably provide a similar combination wherein a protrusion of said housing is extended into said window means and generally between said chock extensions, said sensing means being disposed on said protrusion.

I also desirably provide a similar combination wherein additional sensing means are similarly located between spaced chock extensions on opposite sides of said pair of chocks for averaging purposes.

I also desirably provide a similar combination wherein separating means are coupled directly between said pair of bearing chocks for separating said chocks and said extensions in avoidance of said sensing means during insertion and removal of said rolls and said chocks through said window means.

I also desirably provide a similar combination wherein separation means are coupled directly between said pair of bearing chocks for separating said chocks and said chock extensions in avoidance of said sensing means and said balancing device during insertion and withdrawal of said rolls and said chocks through said window means.

In addition to the references mentioned previously I am also aware of the following patents pertaining in general to rolling mills:

3 ,422,650 Strance 3 ,435,649 OBrien 3 ,490,256 OBrien 3 ,491,5 7l OBrien 3,492,848 Ellis 3 ,496,743 Stone 3 ,5 31,960 Stone 3,550,413 Bamikel The last mentioned group of patents are of interest in that they relate to various arrangements for controlling rolling mill gauge or work roll gap width. These references however do not disclose the novel features of the present invention alluded to above and described below.

During the foregoing discussion, various objects, features and advantages of the invention have been set forth. These and other objects, features and advantages of the invention together with structural details thereof will be elaborated upon during the forthcoming description of certain presently preferred embodiments of the invention and presently preferred methods of practicing the same.

In the accompanying drawings I have shown certain presently preferred embodiments of the invention and have illustrated certain presently preferred methods of practicing the same, wherein;

FIG. 1A and FIG. 1B are partial, composite elevational views, partly in section, of an exemplary mill stand arranged in accordance with the invention;

FIG. 2 is a horizontally sectioned view of the apparatus as shown in FIG. 1A and taken along reference line II--II thereof;

FIG. 3 is a vertically sectioned view of the apparatus as shown in FIG. 2 and taken along reference line III- III thereof;

FIG. 3A is a vertically sectioned view of the apparatus as shown in FIG. 3 and taken along reference line IIIA-IIIA thereof;

FIG. 4 is a sectional view similar to FIG. 2 of a modifled form of a gap sensing and balancing means of the invention; and

FIG. 5 is a vertically sectioned view of the apparatus as shown in FIG. 4 and taken along reference line VV thereof.

With reference initially to FIGS. lA-3 of the drawings the exemplary mill stand 20 of the invention shown therein comprises a pair of mill stand housings, one of which is shown at reference numerals 22 in FIGS. IA, 18. In this case the mill stand housings each include a pair of inwardly extending supports 24 protruding in wardly of the housing window means 26. A pair of backup roll chocks 28, 30 are mounted in each of the housing windows 26. The upper backup roll chocks 28 (only one of which is shown in each of FIGS. 1A, 1B) are maintained against the upper mill screwdowns (not shown) by a pair of backup roll balancing cylinders 32 with one of the cylinders 32 being mounted in each of the Mae West housing supports or protrusions 24.

As shown in FIG. 1A minimum sized backup rolls 34, 36 are mounted in the backup roll chocks 28a, 390, while maximum sized backup rolls 38, 40 are mounted in backup roll chocks 28b, 30b, as evident from FIG. 1B.

A work roll assembly comprising minimum sized work rolls 42, 44 (FIG. 1A) or maximum sized work rolls 46, 48 (FIG. 1B) and their respectively associated bearing chocks 50a, 52a or 50b, 52b are likewise mounted in the housing window means 26. For easy insertion and removal of the aforedescribed roll assembly the lower work roll chocks 52a or 52b are wheel mounted for engagement with a pair of supporting rails 54 mounted on the mill stand housings, for example the housing 22. However, during operation of the mill stand the bottom screwups or equivalent (not shown) are operated to raise the lower backup roll 36 or 40 to lift the work roll assembly free of the rails 54.

Suitable slide or wear plates 56, 58, 60 are mounted on the housing protrusions 24 and on the waist sections of the upper and lower work roll chocks 50a, 52a or 50b, 52b respectively for sliding engagement with the housing protrusions 24, when the aforementioned work roll assembly is inserted into the mill stand 20. In furtherance of this purpose, and to provide a convenient mounting of the sensing means 120 and balancing means 90 described below, the housing protrusions 24 can be extended between the roll chock extensions 114, 116 likewise described below.

FIG. 1A shows the spatial distribution of the various components of the mill stand 20 when employing minimum diameter work rolls and minimum diameter backup rolls. Conversely FIG. 1B shows the spatial arrangement of these components or similar components when maximum diameter work rolls and maximum diameter backup rolls are substituted. In either of these limiting cases, and of course with work and backup rolls of intermediate diameters, the upper back-up roll chocks 280 or 28b are supported by the balancing cylinders 32 until strip material enters the work roll bite or gap along pass line 62 (FIG. 1B). As better shown in FIGS. 1A and 2 the backup roll balancing cylinders 32 can be mounted in the four housing projections 24, such that four balancing cylinders 32 are provided in this case. Each of the cylinders 32 is provided with suitable hydraulic connections adjacent their blank ends 64 (FIG. 1A) to actuate the pistons 66.

In the arrangement of the mill stand 20 as shown each pair of work roll chocks 50a, 52a or 50b, 52b are provided with a number of constant-center chock separators 68. As indicated in FIG. 2, two pairs of the separators 68 are provided in each pair of work roll chocks, with one such pair on each side of the roll necks 70. The separators 68 are intended to separate the two pairs of work roll chocks 50a, 52a, or 50b, 52b during handling of the aforedescribed work roll assembly as a discrete unit during roll changing. The separators 68 maintain the work roll chocks and of course the work rolls contained therein in alignment and at a perdetermined spaced configuration for insertion into the mill.

In one arrangement according to the invention, each of the separators 68 includes a spring loaded plunger 72 loosely fitted in bore 74 of the associated upper work roll chock 500 or 50b. The plunger 72 in this example includes a piston-like backing member 76 closely fitted in the bore 74 and provided with a stop rod 78. Intermediate the ends of the bore 74 a spring stop 80 is mounted and spring means 82 are confined between the spring stop 80 and the adjacent side of the piston member 76. The piston 76 maintains the stop rod 78 and the plunger 72, which are desirably formed integrally with the piston member 76, on a constant center relative to the associated upper bearing chock 50a or 501). Similarly, the plunger 72, which is closely fitted into a shallow bore 84 in the associated lower work roll chock 52a or 52b maintains the separator arrangement 68 on a constant center relative to the lower work roll chock. Thus, the work roll chocks are maintained in alignment by the eight chock separators 68. It will be understood of course that a different number of separators 68 can be employed in a given application of this feature of the invention.

The outward extension of the plunger 72 can be limited by engagement of the piston member 76 with shoulder 86 adjacent the lower end of the bore 74. Alternatively the extension of the plunger 72 can be adjustably limited by engagement of threaded and pinned nut 88 on the upper end portion of the stop rod 78 with the aforementioned stop 80.

The work roll chock separators 68 can take various forms within the teachings of the invention. For example the spring means 82 can be replaced with suitable means for introducing a hydraulic fluid within the bore 74 to actuate the piston members 76.

Once the aforedescribed work roll assembly has been inserted into the mill stand 20, balancing means are provided for forcing the work rolls against the backup rolls. At such time of course the backup balancing cylinders 32 are actuated to raise the upper backup roll 34 or 38 to accommodate movement of the upper work roll 42 or 46 and its associated bearing chocks.

Desirably the work roll balancing means are not secured to either or both of the work roll bearing chocks and therefore need not be disconnected from the work roll assembly or need not be removed therewith as the case may be. A suitable form of work roll balancing device, is better shown in FIG. 1A and to a lesser extent in FIG. 3. A pair of the work roll balancing devices 90 are provided for each pair of the work roll chocks, with one of the devices 90 being mounted in each of the mill housing protrusions 24. Accordingly, a total of four such balancing devices 90 are employed in this example of the invention although a different number can be utilized as required.

Each of the balancing devices 90 includes in this example a cylindrical housing 94 in which a hollow first plunger 92 is reciprocatably mounted as shown. Likewise reciprocatably mounted within the hollow of the plunger 92 is a second plunger in the form of piston 96 having a piston rod 98 sealingly protruded through end closure 100 for the first plunger 92 and loosely fitted through end closure 102 of the cylinder 94. Contact studs 10 4, 106 this example are threadedly engaged with the distal end of the piston rod 98 and with the opposite or outer end of the hollow plunger 92, respectively. A pressurized hydraulic fluid is introduced into plunger chamber 108, through suitable hydraulic connections not shown, to drive the first plunger 92 upwardly as denoted by arrow 110 and the second plunger or piston 96 downwardly as denoted by arrow 112. As evident from FIG. 1A the contact members 104, 106 bearingly engage the juxtaposed work roll chock extensions 114, 116 respectively to force the work roll chocks apart as required to force the work rolls against the backup rolls.

The balancing devices 90 can be supported in any convenient manner but desirably and generally between the work roll extensions 114, 116. Further considerations of the mounting of the balancing devices 90 is the positioning thereof such that their contact members 104, 106 are disposed in a bearing but nonsecurance engagement with the work roll projections 114, 116 respectively. The cylinder portion 94, therefore, need not be rigidly mounted on the housing protrusions 24. Instead, the housing protrusions 24 can be eliminated and the cylinder components 94 of the balancing devices 90 can be spring clipped or otherwise secured by suitable brackets directly to the edge of a rectangular housing window (not shown) of the mill stand housing, or to some other stationary component of the mill stand. Alternatively, the cylinders 94 of the balancing devices 90 can be spring clipped (not shown) or otherwise secured directly to one of the waist portions 122, 124 of the work roll chocks.

The work roll balancing devices 90 thus are stationarily mounted on the mill stand and need not be directly connected to the work roll chocks. The second plunger or pistons 96 desirably are double acting such that upon relaxation of the pressure in the plunger changers 108, pressurized hydraulic fluid can be admitted through suitable hydraulic connections (not shown) into the plungers 92 of the other side of the pistons 96 to collapse the balancing devices 90, when required. On the other hand the hollow plungers 92 can be forceably withdrawn or collapsed if necessary by the backup roll assemblies when it is desired to change position of the work rolls.

The top backup roll balance cylinders are energized along with de-energization of the work roll balance. The bottom backup roll assembly and the entire work roll assembly are then lowered until the work roll chock wheels engage the mill stand rails 54. At this time with suitable manipulation of the work roll clamps, work roll assembly can be freely inserted or removed relative to the mill stand 20 without interference by or with the retracted balancing devices 90.

As explained previously, it is highly desirable to provide an instantaneous indication of work roll position such that the thickness of the strip passing through the mill stand 20 can be continuously monitored. Owing to considerations of mill modulus and other variables mentioned previously, it is highly desirable to measure the work roll gap from a position as close to the work roll bite as is feasible. Desirably also the work roll position indicator or sensing means has a sufficient throw or travel such that the same sensing means can be utilized for a wide variation in work roll gaps (although such wide variation usually does not occur), but more particularly so that the same position sensor can be employed with that range of work roll diameters (e.g. work rolls 42-46 and 44-48) and backup roll diameters for which the mill stand 20 is designed.

An unexpected but convenient location of the sensing arrangement of the invention is a disposition of the sensors generally between the work roll chock projections 114, 116. It is also in accord with the invention that at least the supporting means or contact engaging means for the work roll sensing means be so located. Accordingly movements of the work roll chocks are indicated by the sensing means, and these movements are closely indicative of the work roll gap and hence changes in the strip thickness.

One advantage for so locating the work roll sensing means 120 or their supporting or contacting means (FIGS. 1B, 2 and 3) is their location as close to the work roll bite as feasible without interference by or with the strip moving along pass line 62. With these considerations in mind the sensors 120 can be mounted for actuation by movements of the work roll chock extensions 114, 116. For example, the sensors 120 can be provided with a stationary sheath (not shown) and attached by spring clips (not shown) secured to one of the waist portions 122, 124 of the roll chocks 50a, 52a or 50b, 52b. Alternatively the sensing devices 120 can be similarly mounted directly on the housing protrusions 24 for a non-securance contact with the work roll extensions 114, 116. Alternatively again, and preferably, the sensing devices 120 are respectively mounted or suspended from the work roll balancing devices 90, for movement of their operative components therewith. A further feature of this preferred mode of operation is the juxtaposition of the sensing devices 120 with the housing protrusions 24 such that the operative components of the sensing devices 120 can move freely with respect to the housing protrusions 24 in conformance with movements of the work roll chocks, but such that the sensors themselves are protectively enclosed by the housing protrusions 24 and associated components described presently.

Accordingly, the sensing devices 120, which are provided with a movable casing 126 and a movable actuating rod 128, in this arrangement of the invention, can be suspended from similarly movable components of the associated balancing device 90. One arrangement for so suspending each of the work roll sensors 120 includes a pair of actuating arms 130, 132 secured to the ends respectively of the movable sensor rod 128 and of stud 134 secured to sensor casing 126 for movement therewith. The other ends of the actuating arms 130, 132 are secured to the contact members 106, 104 of the associated balancing device for movement therewith. The actuating arms 130, 132 are sufficiently rigid that the rod 128 and stud 134 precisely follow the movements of the work roll chock extensions 114, 116 respectively. The mechanical relationships between the sensing device and the balancing device 90 are indeed unique, as the balancing device 90, in addition to its function in separating the work roll chocks when required and in suspending the sensor 120, maintains bearing contact of the moving components of the sensor with the work roll chock extensions 114, 116 through the actuating arms 130, 132 and the contact members 104, 106 respectively of the associated balancing device. As set forth below with reference to FIG. 3A, the casing 126 for the various components of the sensor 120 is movably supported entirely by the balancing device 90 through the lower actuating arm 132 and the contact member 106 thereof. The actuating arms 130, 132 can be welded or shrunk fitted to the contact members 104, 106, or otherwise fastened as desired.

Also shown in FIGS. 18, 2, 3 is the protective juxtaposition of each of the work roll sensors 120 relative to the associated housing protrusion 24, its slide block 136 and clamp means or members 138 of the work roll chocks. The primary purpose of each slide block 136 is the retention of the clamp members 138 between a notched portion 140 of the associated housing protrusion 24 and the slide block 136. Suitable clearances are left between the slide block 136, the housing protrusion notch 140, and the chock clamping members 138 as shown in FIG. 2.

'Desirably the housing protrusion notch 140 is deepened to accommodate the associated work roll sensor 120 as best shown in FIG. 2. The sensor 120 thus is protected from mechanical injury by the adjacent surfaces of the housing protrusion 24, the slide block 136, which is spaced slightly from the movable sensor casing 126 and the end surfaces of the work roll chock clamps 138, which are likewise spaced from the sensor casing 126 to accommodate any relative movement therebetween without physical contact with the casing 126. The sensor 120 is thus loosely confined within the housing protrusion notch 140 and the associated components in such manner that there is no interference with the movable components of the sensor.

As shown in FIGS. 1B, 2 the slide block 136 is provided with a slide plate 142 whereby the slide block 136 can be manipulated for purposes which will now be described. The slide plate 142 is rigidly secured to the slide block 136 as by welding or by integral casting or the like, and slideably overlies an adjacent structure 144 of the housing 22. The slide plate 142 can be readily grasped for manipulation of the slide block 136. When the slide plate and block are withdrawn to the position of their inward edges as denoted by chain line 148 (FIG. 2) the aforedescribed work roll assembly can be withdrawn as the slide block and plate no longer are in a position to contact the outward end portions of the work roll chock clamps 138. However, the slide blocks 136 still protectively overly the associated work roll sensors 120. When the slide plate and block are withdrawn further such that their inward edges are positioned at chain line 150 the associated sensor 120 is now exposed for inspection, maintenance or removal. It is also evident that the sensor 120 can be readily replaced once the slide block is withdrawn to its position at 150 simply by removing retaining nuts 151, 153 respectively from the rods 128, 134 of the sensor.

The sensors 120 can take a variety of forms of position indicators in keeping with the teachings of related features of the invention. By the same token the configurations of the actuating arms 130, 132 the housing protrusion slot 140 and the slide block 136 can be modified for a given size or shape of the associated sensor 120. Desirably, however, the sensor is capable of developing a variable electric signal, whose variation is very closely related to displacements of the work roll chock 50a, 52a, or 50b, 52b.

A preferred form of the sensors 120 is illustrated in FIG. 3A. As mentioned previously the movably supported casing 126 is provided with a mounting stud 134 secured in this example to the lower actuating arm 132 (as viewed in FIGS. 3, 3A). Movable actuating rod 128 is closely fitted through end closure 1152 for the casing 126 and sleeve bearing 154 secured thereto and a second bearing 156 mounted within the casing 126 intermediate the ends thereof. The bearing 156 is sufficiently displaced from the opposite end of the casing 126 to afford a sufficient range of movement to coil member 158 secured to the movable rod 128 for movement therewith. The bearing members 154, 156 are disposed such that an exact spacing is maintained between the movable coil member 158 and a stationary coil member 160 secured to an inner wall surface of the casing 126 and extending longitudinally thereof. Alternatively, the inner bearing member 156 can be omitted and the inward end portion of the movable rod 128 can be extended into the supporting stud 134 for the casing 126, which stud can be provided with a longitudinal hollow passage 162 for this purpose.

As the movable coil member 158 traverses the stationary coil member 160, a fluctuating electrical signal is produced of discrete, displaced sign waves or the like owing to the voltages generated in both of the coil members 158, 160. By measuring the amplitudes of the sign waves and by counting the numbers of discrete sign waves a very precise indication of work roll chock position can be determined from the character of the output signal. Of prime importance is the fact that the response period of the sensor of FIG. 3A is of the order of only l/20th that of a typical load cell. Thus, a more accurate and immediate indication of strip gauge can be determined from the sensors 120.

The configuration, disposition, and operation of the individual coils making up the coil members 158, 160 and the character of their output signals are essentially identical to sensors sold by Farrand Controls, Inc. of Valhalla, N.Y. under the trademark, Inductosyn, and need not be further described at this point, for an understanding of the FIG. 3A embodiment.

To prevent entry of foreign matter through the necessary clearances between the actuating rod 128 and the casing end closure 152 an air pressure of slight gauge can be maintained within the movably supported casing 126 through suitable conduit means 164 and housing aperture 166.

With reference now to FIGS. 4 and 5 of the drawings the sensor 120 is shown in similar association with a modified form of the balancing device 90'. The balancing device 90' is similarly disposed in housing protrusion 24, more or less after the manner of the preceeding figures. In this arrangement, however, the balancing device includes an opposed pair of cylinder arrangements 168, 170, having opposed plunger or pistons respectively and reciprocatably mounted therein. The distal end of upper piston rod 172 bears against work roll chock projection 114' while the distal end of lower piston rod 174 bears against work roll chock extension 116'. Actuating arms 130, 132 are connected to the piston rods 172, 174 and the work roll sensor 120 as shown. A suitable branched hydraulic conduit denoted schematically at 176 connects the pressure chambers 178, 180 of the cylinder arrangements 168, with a suitable source of pressurized hydraulic fluid. Thus, the plungers of the cylinder arrangements 168, 170 are actuated in opposite direction such that their rods 172, 174 bearingly engage the work roll extensions 114', 116' and similarly actuate the sensor 120, for the purposes described previously.

From the foregoing it will be apparent that novel and efficient forms of Work Roll Sensing and/or Balancing Arrangements have been described herein. While I have shown and described certain presently preferred embodiments of the invention and have illustrated presently preferred methods of practicing the same it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the spirit and scope of the disclosure.

I claim:

1. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said chock extensions which are respectively and spacedly disposed on said pair of said work roll Chocks, means for removably mounting said sensing means on a support mounted on said housing means and juxtaposed to said chock extensions, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith.

2. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, said sensing means being positioned on a housing protrusion extending into said window means.

3. The combination according to claim I wherein said sensing means and at least an adjacent portion of said housing support are positioned generally between said pair of chock extensions.

4. The combination according to claim 3 wherein said housing support includes a work roll balancing device for bearingly engaging said pair of extensions.

5. The combination according to claim 1 wherein said engaging means include a pair of opposed plungers disposed for hearing contact with said chock extensions, and said movable components of the sensing means are secured to said plungers respectively for movement therewith.

6. The combination according to claim 2 wherein said sensing means are disposed between said housing protrusion and a slide member mounted thereon, said slide member being movable to a position to expose said sensing means for inspection, maintenance or removal.

7. The combination according to claim 6 wherein said housing protrusion and said slide member are further configured to accommodate clamp means therebetween, said clamp means being secured to said pair of chocks.

8. The combination according to claim 7 wherein said housing protrusion and said slide member and said clamp means are further configured to substantially surround said sensing means.

9. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, means for suspending said sensing means generally between said pair of chock extensions, said suspending means including a work roll balancing device for bearingly engaging said pair of extensions, and said balancing device including a cylinder mounted on a protrusion of said housing support extending into said window means, a hollow first plunger reciprocatably mounted in said cylinder and disposed for hearing engagement with a juxtaposed one of said chock extensions, a second plunger reciprocatably mounted within said first plunger and disposed for bearing engagement with the other of said chock extensions, said sensing means components being suspended from said first and said second plungers respectively for movement therewith and for support thereby.

10. The combination according to claim 4 wherein said balancing device includes a pair of opposed and discrete cylinder arrangements mounted in a housing protrusion extending into said window means, and discrete plungers respectively and reciprocatably mounted in said arrangements and disposed for bearing contact with said pair of extensions respectively, said sensing means movable components being secured to said plungers respectively for movement therewith and for support thereby.

11. The combination according to claim 2 wherein said housing protrusion in addition extends generally between said chock extensions.

12. The combination according to claim 1 wherein additional sensing means are similarly located between spaced chock extensions on opposite sides of said pair of chocks for averaging purposes.

13. The combination according to claim 1 wherein additional sensing means are similarly located between spaced chock extensions of a pair of bearing chocks at opposite end portions of said work rolls for averaging purposes.

14. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, means for suspending said sensing means generally between said pair of chock extensions, said suspending means including a work roll balancing device for bearingly engaging said pair of extensions, and a housing protrusion extending generally between said pair of chock extensions, and said balancing device being mounted on said housing protrusion at a location between said extensions.

15. The combination according to claim 14 wherein said sensing means and said balancing device are located on said housing protrusion in avoidance of said bearing chocks during insertion and removal of said rolls and said chocks through said window means.

16. The combination according to claim 1 wherein said sensing means include a movably mounted housing, a support and contact member rigidly secured to said housing for movement therewith, a movable contact rod slideably inserted into said housing, and a pair of coil members secured to said housing and to said rod for movement therewith respectively.

17. The combination according to claim 16 wherein said support and contact member is provided with a longitudinally extending passage, and said rod is slideably inserted into said passage.

18. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, said sensing means including a movably mounted housing, a support and contact member rigidly secured to said housing for movement therewith, a movable contact rod slidably inserted into said housing, a pair of coil members secured to said housing and to said rod for movement therewith respectively, said support and contact member being provided with a longitudinally extending passage, said rod being slidably inserted into said passage, and conduit means coupled in communication with said sensing means housing for maintaining a slight gauge air pressure therein against entry of foreign matter.

19. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, and separating means coupled directly between said pair of bearing chocks for separating said chocks and said extensions in avoidance of said sensing means during insertion and removal of said rolls and said chocks through said window means.

20. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, means for suspending said sensing means generally between said pair of chock extensions, said suspending means including a work roll balancing device for bearingly engaging said pair of extensions, and separating means coupled directly between said pair of bearing chocks for separating said chocks and said chock extensions in avoidance of said sensing means and said balancing device during insertion and withdrawal of said rolls and said chocks through said window means. 

1. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said chock extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for remOvably mounting said sensing means on a support mounted on said housing means and juxtaposed to said chock extensions, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith.
 2. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, said sensing means being positioned on a housing protrusion extending into said window means.
 3. The combination according to claim 1 wherein said sensing means and at least an adjacent portion of said housing support are positioned generally between said pair of chock extensions.
 4. The combination according to claim 3 wherein said housing support includes a work roll balancing device for bearingly engaging said pair of extensions.
 5. The combination according to claim 1 wherein said engaging means include a pair of opposed plungers disposed for bearing contact with said chock extensions, and said movable components of the sensing means are secured to said plungers respectively for movement therewith.
 6. The combination according to claim 2 wherein said sensing means are disposed between said housing protrusion and a slide member mounted thereon, said slide member being movable to a position to expose said sensing means for inspection, maintenance or removal.
 7. The combination according to claim 6 wherein said housing protrusion and said slide member are further configured to accommodate clamp means therebetween, said clamp means being secured to said pair of chocks.
 8. The combination according to claim 7 wherein said housing protrusion and said slide member and said clamp means are further configured to substantially surround said sensing means.
 9. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, means for suspending said sensing means generally between said pair of chock extensions, said suspending means including a work roll balancing device for bearingly engaging said pair of extensions, and said balancing device including a cylinder mounted on a protrusion of said housing support extending into said window means, a hollow first plunger reciprocatably mounted in said cylinder and disposed for bearing engagement with a juxtaposed one of said chock extensions, a second plunger reciprocatably mounted within said first plunger and disposed for bearing engagement with the other of said chock extensions, said sensing means components being suspended from said first and said second plungers respectively for movement therewith and for support thereby.
 10. The combination according to claim 4 wherein said balancing device includes a pair of opposed and discrete cylinder arrangements mounted in a housing protrusion extending into said window means, and discrete plungers respectively and reciprocatably mounted in said arrangements anD disposed for bearing contact with said pair of extensions respectively, said sensing means movable components being secured to said plungers respectively for movement therewith and for support thereby.
 11. The combination according to claim 2 wherein said housing protrusion in addition extends generally between said chock extensions.
 12. The combination according to claim 1 wherein additional sensing means are similarly located between spaced chock extensions on opposite sides of said pair of chocks for averaging purposes.
 13. The combination according to claim 1 wherein additional sensing means are similarly located between spaced chock extensions of a pair of bearing chocks at opposite end portions of said work rolls for averaging purposes.
 14. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, means for suspending said sensing means generally between said pair of chock extensions, said suspending means including a work roll balancing device for bearingly engaging said pair of extensions, and a housing protrusion extending generally between said pair of chock extensions, and said balancing device being mounted on said housing protrusion at a location between said extensions.
 15. The combination according to claim 14 wherein said sensing means and said balancing device are located on said housing protrusion in avoidance of said bearing chocks during insertion and removal of said rolls and said chocks through said window means.
 16. The combination according to claim 1 wherein said sensing means include a movably mounted housing, a support and contact member rigidly secured to said housing for movement therewith, a movable contact rod slideably inserted into said housing, and a pair of coil members secured to said housing and to said rod for movement therewith respectively.
 17. The combination according to claim 16 wherein said support and contact member is provided with a longitudinally extending passage, and said rod is slideably inserted into said passage.
 18. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, said sensing means including a movably mounted housing, a support and contact member rigidly secured to said housing for movement therewith, a movable contact rod slidably inserted into said housing, a pair of coil members secured to said housing and to said rod for movement therewith respectively, said support and contact member being provided with a longitudinally extending passage, said rod being slidably inserted into said passage, and conduit means coupled in communication with said sensing means housing for maintaining a slight gauge air pressure therein against entry of foreign matter.
 19. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chOcks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, and separating means coupled directly between said pair of bearing chocks for separating said chocks and said extensions in avoidance of said sensing means during insertion and removal of said rolls and said chocks through said window means.
 20. In a rolling mill stand having housing means, window means in said housing means, and a pair of work rolls having bearing chocks for rotatably supporting ends of the work rolls in said window means, the combination comprising at least one extension on each of an adjacent pair of said bearing chocks, position sensing means disposed generally between a pair of said extensions which are respectively and spacedly disposed on said pair of said work roll chocks, means for removably mounting said sensing means on said mill stand, and means for bearingly and respectively engaging movable components of said sensing means with said pair of extensions for movement therewith, means for suspending said sensing means generally between said pair of chock extensions, said suspending means including a work roll balancing device for bearingly engaging said pair of extensions, and separating means coupled directly between said pair of bearing chocks for separating said chocks and said chock extensions in avoidance of said sensing means and said balancing device during insertion and withdrawal of said rolls and said chocks through said window means. 